Department of Electrical and Computer Engineering, Kulliyyah of Engineering, International Islamic University Malaysia, Kuala Lumpur 53100, Malaysia.
XLIM-UMR 7252, University of Limoges/CNRS, 87060 Limoges, France.
Biosensors (Basel). 2021 Dec 3;11(12):494. doi: 10.3390/bios11120494.
Diabetes has become a major health problem in society. Invasive glucometers, although precise, only provide discrete measurements at specific times and are unsuitable for long-term monitoring due to the injuries caused on skin and the prohibitive cost of disposables. Remote, continuous, self-monitoring of blood sugar levels allows for active and better management of diabetics. In this work, we present a radio frequency (RF) sensor based on a stepped impedance resonator for remote blood glucose monitoring. When placed on top of a human hand, this RF interdigital sensor allows detection of variation in blood sugar levels by monitoring the changes in the dielectric constant of the material underneath. The designed stepped impedance resonator operates at 3.528 GHz with a Q factor of 1455. A microfluidic device structure that imitates the blood veins in the human hand was fabricated in PDMS to validate that the sensor can measure changes in glucose concentrations. To test the RF sensor, glucose solutions with concentrations ranging from 0 to 240 mg/dL were injected into the fluidic channels and placed underneath the RF sensor. The shifts in the resonance frequencies of the RF sensor were measured using a network analyzer via its S parameters. Based on the change in resonance frequencies, the sensitivity of the biosensor was found to be 264.2 kHz/mg·dL and its LOD was calculated to be 29.89 mg/dL.
糖尿病已成为社会的主要健康问题。侵入性血糖仪虽然精确，但由于对皮肤造成的损伤以及一次性用品的昂贵成本，只能在特定时间提供离散测量，不适合长期监测。远程、连续、自我监测血糖水平可以让糖尿病患者更积极地进行管理。在这项工作中，我们提出了一种基于阶跃阻抗谐振器的射频（RF）传感器，用于远程血糖监测。当放置在人手顶部时，这种 RF 叉指传感器通过监测下方材料介电常数的变化来检测血糖水平的变化。设计的阶跃阻抗谐振器在 3.528 GHz 下工作，Q 因数为 1455。在 PDMS 中制造了模仿人手血管的微流控器件结构，以验证传感器可以测量葡萄糖浓度的变化。为了测试 RF 传感器，将浓度范围为 0 至 240 mg/dL 的葡萄糖溶液注入流道并放置在 RF 传感器下方。使用网络分析仪通过其 S 参数测量 RF 传感器的共振频率偏移。基于共振频率的变化，得出生物传感器的灵敏度为 264.2 kHz/mg·dL，其 LOD 计算为 29.89 mg/dL。
